Epigenomics is the study of the complete set of epigenetic modifications on the genetic material of a cell, known as the epigenome. Epigenetic modifications are reversible modifications on a cell’s DNA such as DNA methylation or histones that affect gene expression without altering the DNA sequence.

DNA methylation biomarkers are epigenetic markers (see epigenomics) and analyze methylation levels, which increase with advancing age, at CpG sites, spots on the DNA where methyl groups attach. Zymo received an exclusive license for Horvath’s “epigenetic age” clock in 2016 and sells myDNAage kits. Steve Horvath, is a geneticist and biostatistician at the University of California, Los Angeles.

Histone Modification is the process of adding or removing histone molecules from DNA which affects gene expression without altering the DNA sequence.

Metabolomics is the scientific study of chemical processes and involves the comprehensive detection and identification of metabolites. The metabolome represents the collection of all metabolites in a biological cell, tissue, organ or organism, which are the end products of cellular processes.

Targeted metabolomics is the quantitative study of a small number of metabolites, typically related by chemical or biological similarity. Targeted profiling separates a limited number of specific metabolites of known identity and is a more hypothesis-driven approach.

Untargeted Metabolomic Profiling involves the use of multiple analytical assays (NMR, MS) to measure as many metabolites as possible in a biological sample. Untargeted metabolomic experiments are often hypothesis generating rather than hypothesis driven.

They are often used interchangeably. Strictly speaking, the microbiota is the collection of microorganisms present in a defined environment and it does not refer to the genes or genomes of those microorganisms. The microbiome, and also the metagenome, is defined as the collection of genes and genomes of members of a microbiota. Metagenomics is the study of microbial communities sampled directly from their natural environment (earth, animal/human tissues or fluids), without prior culturing. Metagenomics is the study that provides access to the functional gene composition of microbial communities, it detects the collection of genomes and genes from the members of a microbiota. This collection is obtained through shotgun sequencing of DNA extracted from a sample (metagenomics) followed by assembly or mapping to a reference database followed by annotation.

Transcriptomics is the study that identifies mRNA sequences, the product of gene transcription. Microarrays, are the mainstream technology of the last decade, are used to provided hundreds of valuable transcriptome datasets. RNA-seq, is the current next generation sequencing approach that extends the capabilities of microarrays to analysis of alternative splicing and discovery of novel transcripts

The proteome is the entire set of proteins, produced or modified by an organism or system. This varies with time and distinct exposures, or stresses, that a cell or organism undergoes.

Radiomics enables the high-throughput extraction of a large amount of quantitative features from medical images of a given modality (e.g. CT, PET, or MR), providing a comprehensive quantification of the tumor phenotype, based on simple medical imaging. Radiomics can provide complementary and interchangeable information compared to other sources (e.g. demographics, pathology, blood biomarkers, or genomics), improving individualized treatment selection and monitoring.